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Finding the Fourth Proportional to 640.56, 880.14 and 509.34

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Solution

The fourth proportional to 640.56, 880.14 and 509.34 is: 699.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.56 : 880.14 = 509.34 : x
  2. Step 2: Convert to fraction form
    640.56/880.14 = 509.34/x
  3. Step 3: Cross multiply
    640.56x = 880.14 × 509.34
  4. Step 4: Simplify right side
    640.56x = 448,283.56
  5. Step 5: Solve for x
    x = 448,283.56/640.56
  6. Step 6: Final answer
    x = 699.84

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.